Laser Vision Correction
Laser Vision Correction is a procedure that uses a computer controlled ultra-violet beam of light to reshape the cornea in an effort to allow light to focus more directly on the retina. The procedure first gained acceptance in the mid 1980’s and has undergone numerous clinical trials since that time to refine its use and determine its safety and effectiveness.
It is important that patients have realistic expectations and that decisions are made based on facts – not hopes or misconceptions. Laser Vision Correction does not always create 20/20 or even 20/40 vision. Your doctor will provide you with additional information that will allow you to make an informed decision. In general, the ideal patient has a healthy cornea and has not had a significant increase in their prescription in the last year.
There are two main types of correction being preformed via laser: (1) PRK and (2) LASIK.
Photo-Refractive Keratectomy or PRK treats refractive errors by removing tissue from the surface of the cornea. The surgeon first removes the epithelium, a thin layer of protective skin that covers the cornea, then the laser is applied to the underlying layers to reshape the surface of the cornea. The procedure only takes a few minutes. By altering the shape or placement of the laser beam, the cornea is made flatter to treat near-sightedness, steeper to treat farsightedness and/or more spherical to treat astigmatism.
Laser in-Situ Keratomileusis or LASIK differs from PRK in that it corrects vision by reshaping the corneal tissue beneath the surface of the cornea. Rather than remove the surface layer of the cornea, a special device called a microkeratome is used to create a thin corneal flap of tissue. The laser is applied to the underlying tissue and the flap is then repositioned. LASIK can be used to treat higher levels of nearsightedness and moderate amounts of farsightedness, however, there are limits. Similar to PRK, the cornea is made flatter to treat nearsightedness, steeper to treat farsightedness and more spherical to treat astigmatism. Because LASIK is performed under a protective layer of tissue, there is less surface area to heal, less risk of corneal haze, less postoperative discomfort and medication, and vision returns more rapidly. However, LASIK carries additional surgical risks than PRK. Talk to your eye doctor to learn more.